NPE and OpCo Filings Increased for Second Year in a Row in 2025

NPEs added 2,236 defendants to patent litigation campaigns in 2025, an increase of 18.7% compared to 2024 (when such plaintiffs added 1,884 defendants)—which, in turn, saw 22% more NPE litigation than 2023. Operating companies added 1,190 defendants last year, up 10.7% from 2024; that year was also up compared to 2023 for such plaintiffs, albeit by a more modest 9%. Overall, 3,426 defendants were added to litigation campaigns in 2025, or 15.8% more than the year before (at 2,959 defendants added).

In the fourth quarter, NPEs added 524 defendants, or 7% more than Q4 2024—exceeding the trailing three-quarter Q4 average for 2022-2024 by 10%, but staying essentially flat compared to Q3 2025. Meanwhile, operating companies added 344 defendants in Q4, a 26% increase compared to the fourth quarter last year. Operating company filings last quarter were also 26% higher than in Q3 2025 and were 10% greater than the trailing Q4 average.

Overall, patent plaintiffs added 868 defendants in the fourth quarter of 2025, or 13% more than in Q4 2024 and 8% more than Q3 2025, also beating the trailing average by 10%.

See RPX’s fourth-quarter review for more on district court filings in Q4 and 2025, as well as other key trends that shaped patent litigation last year.